JPH08304838A - Production of liquid crystal display element and sealing agent - Google Patents

Abstract

PURPOSE: To provide a producing method of a liquid crystal display element to produce a liquid crystal display element with little display irregularity and to provide a sealing agent showing little shrinkage during it is hardened. CONSTITUTION: The sealing agent 16 consists of a mixture of a thermosetting or UV-curing resin 17 and solid particles such as a glass fiber 18. After a liquid crystal cell 10 is formed, a liquid crystal 14 is injected through the injection port of the liquid crystal cell into the cell 10. Then the sealing agent 16 is supplied to fill the liquid crystal injection port and then hardened. In this process, although the resin 17 is shrunk, the solid particles such as a glass fiber 18 does not shrink but prevents the resin 17 from shrinking. Therefore, no pressure due to shrinkage of the sealing agent 16 is added between the substrates 11, 12 near the liquid crystal injection port, so that a uniform distance between the substrates 11, 12 can be maintained and the thickness of the liquid crystal 14 layer can be maintained uniform. Therefore, irregular display can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device capable of reducing the unevenness of the cell gap of a liquid crystal cell when the liquid crystal is injected into the liquid crystal cell and the injection port is sealed, and a method for using the same. The present invention relates to a sealing agent.

[0002]

2. Description of the Related Art Generally, a liquid crystal display device has a substrate 11 made of a pair of glass or plastic on which electrodes and alignment films are formed, as shown in a cross section of FIG. 4 and a plane of FIG.
The liquid crystal cell 10 is formed by bonding 12 through the seal material 13, and the liquid crystal 14 is injected into the liquid crystal cell 10 from the liquid crystal injection port 15 arranged in the seal material 13 by a vacuum injection method or the like. Lastly, the liquid crystal injection port 15 is formed by sealing with a sealant 16.

[0003]

As the sealant 16,
A thermosetting resin such as an epoxy resin or an ultraviolet curable resin is used. This type of resin shrinks when cured. Therefore, in the conventional method for manufacturing a liquid crystal display element, the sealing agent 1
6 is cured, as shown in FIG.
The two intervals, that is, the layer thickness of the liquid crystal 14 is uniform. However, when the sealant 16 hardens, the sealant 16 contracts, and as shown in FIG. 5, the seal material 13 is used as a fulcrum, and the gap between the substrates 11 and 12, that is, the liquid crystal 14 is set by the lever principle. The layer becomes thick, and a region 21 where display unevenness occurs is formed near the liquid crystal injection port 15.

The present invention has been made in view of the above circumstances, and provides a method of manufacturing a liquid crystal display device capable of manufacturing a liquid crystal display device having no display unevenness in the vicinity of the liquid crystal injection port and having little display unevenness as a whole. The purpose is to Another object of the present invention is to provide a sealant having a small shrinkage upon curing as a sealant for sealing a liquid crystal injection port of a liquid crystal display element.

[0005]

In order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention comprises a step of forming a liquid crystal cell having a liquid crystal injection port, and a step of forming a liquid crystal cell in the liquid crystal cell from the liquid crystal injection port. A step of injecting liquid crystal, a step of filling the liquid crystal injection port with a sealant composed of an uncured resin containing a predetermined amount of solid particles, and the shrinkage of the sealant while suppressing shrinkage by the solid particles. A curing step of curing and sealing the liquid crystal injection port.

The sealant for sealing the liquid crystal injection port of the liquid crystal display element according to the present invention is an ultraviolet curable resin and a curable resin containing at least one of the ultraviolet curable resin,
It is characterized by comprising solid particles mixed in the curable resin.

[0007]

The sealant according to the present invention contains solid particles such as glass fibers and cured resin pellets, and the solid particles prevent the resin from shrinking when it is cured. Therefore, it is possible to obtain a sealant having a small shrinkage factor when the sealant is cured. Then, by sealing the liquid crystal injection port with this sealant, it is possible to prevent unevenness in the substrate interval and prevent uneven display.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a liquid crystal display element according to an embodiment of the present invention will be described below with reference to the drawings. FIG.
FIG. 4 is a cross-sectional view of a portion near a liquid crystal injection port of the liquid crystal display element of this example. In this embodiment, as in the conventional case, after the liquid crystal 14 is injected into the liquid crystal cell 10 shown in FIG. 6 from the liquid crystal injection port 15 by a vacuum injection method or the like, as the sealant 16 for sealing the liquid crystal injection port 15, heat is applied. Curable or UV curable resin 1
The glass fiber 18 mixed in 7 is used.

The glass fiber 18 is made of glass or plastic and has a length of 40 μm to 100 μm.
And has a diameter of about 5 to 10 μ, and 2 to 5% by weight.
To some extent, it is mixed in the thermosetting or ultraviolet curable resin 17.

According to this structure, the liquid crystal injection port 15 formed in the seal material 13 is sealed with the uncured sealant 16, and the resin 17 tends to shrink when it is cured. However, the glass fiber 18 prevents the contraction. Therefore, almost no force due to contraction is applied between the substrates 11 and 12 near the liquid crystal inlet 15. Therefore, the sealing agent 16
Even after curing the substrate, as shown in FIG.
The space between will not expand. Therefore, the thickness of the layer of the liquid crystal 14 is maintained uniform over the entire area, and display unevenness of the liquid crystal display element can be prevented.

Next, a method of manufacturing the liquid crystal display element of this embodiment will be described. First, an electrode, an alignment film, and the like are formed on the opposing surfaces of the one substrate 11 and the other substrate 12, respectively. In the case of an active matrix type liquid crystal display element, active elements and the like are also formed.

Subsequently, a spacer is sprinkled on one of the substrates 11, and a seal material 13 made of a thermosetting resin, an ultraviolet curable resin or the like is printed. At this time, the liquid crystal injection port 15 is formed in the seal material 13. Then, the substrate 11
And 12 are joined and heated or irradiated with ultraviolet rays to obtain a seal material 1
3 is cured to form the liquid crystal cell 10.

Then, the liquid crystal 14 is injected into the liquid crystal cell 10 through the liquid crystal injection port 15 by using a vacuum injection method or the like. And
After adjusting the layer thickness of the liquid crystal 14, the liquid crystal injection port 15
To the uncured resin 17 including the glass fiber 18 described above.
The sealant 16 consisting of is filled and applied. Then, the sealant 1
When the resin 17 constituting 6 is a thermosetting resin, it is heated, and when it is ultraviolet curable, it is irradiated with ultraviolet rays to cure the resin 17. Thereby, the liquid crystal injection port 15 is sealed. At this time, the resin 17 tries to shrink, but the glass fiber 18 does not shrink, preventing the resin 17 from shrinking.
Therefore, as shown in FIG. 2, the gap between the substrates 11 and 12 is maintained uniform, and the layer thickness of the liquid crystal 14 is also maintained at a constant value over the entire enclosed region inside the seal material 13.

Subsequently, necessary processing such as arranging a polarizing plate, a retardation plate, a reflecting plate, etc. is performed to complete the liquid crystal display element.

As described above, according to the liquid crystal display element and the method of manufacturing the same of the present embodiment, the layer thickness is maintained uniform over the entire liquid crystal 14 filling area including the vicinity of the liquid crystal injection port 15 and the display unevenness thereof. Can be prevented.

The present invention is not limited to the above embodiment, and various modifications and applications are possible. For example, in the above-described embodiment, the glass fiber 18 is mixed into the thermosetting or ultraviolet curable resin 17 to prevent the resin 17 from contracting during curing, but the resin is not limited to the rod-shaped solid particles such as the glass fiber 18. For example, as shown in FIG. 3, cured resin pellet particles 19 or spherical solid particles such as glass beads may be mixed. Further, rod-shaped solid particles and spherical solid particles may be mixed.

Glass fiber 18 mixed with resin 17
The size and weight of the cured resin pellets 19 and the cured resin pellets 19 are not limited to those in the above embodiment, and various modifications are possible. Further, the present invention can be applied to a simple matrix type liquid crystal display element and an active matrix type liquid crystal display element.

[0018]

As described above, according to the present invention, when the liquid crystal injection port of the liquid crystal cell is sealed, the solid particles suppress the shrinkage of the sealant during curing, so that a uniform liquid crystal is obtained. It is possible to obtain a liquid crystal display element having a layer thickness and no display unevenness, and moreover, the liquid crystal injection port can be surely sealed. Also,
According to the present invention, it is possible to provide a sealant for liquid crystal display elements having a small shrinkage rate.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross-sectional structure of a liquid crystal display element according to an embodiment of the present invention before curing of a sealing agent.

FIG. 2 is a view showing a cross-sectional structure of the liquid crystal display element according to the embodiment of the present invention after the encapsulant is cured.

FIG. 3 is a diagram showing a cross-sectional structure of a liquid crystal display element for explaining a sealing agent for a liquid crystal display element according to another embodiment of the present invention.

FIG. 4 is a diagram showing a cross-sectional structure of a conventional liquid crystal display element before curing of a sealant.

FIG. 5 is a diagram showing a cross-sectional structure of a conventional liquid crystal display element after curing of a sealing agent.

FIG. 6 is a plan view for explaining a planar structure and display unevenness of a conventional liquid crystal display element after a sealant is cured.

[Explanation of symbols]

10 ... Liquid crystal cell, 11 ... Substrate, 12 ... Substrate, 13 ...
Sealant, 14 ... Liquid crystal, 15 ... Liquid crystal inlet, 16 ...
Sealant, 17 ... Thermosetting or UV curable resin, 1
8 ... Glass fiber, 19 ... Cured resin pellet particles, 21 ... Part where display unevenness occurs

Claims (5)

[Claims] 1. A step of forming a liquid crystal cell having a liquid crystal injection port, a step of injecting liquid crystal into the liquid crystal cell through the liquid crystal injection port, and a seal made of an uncured resin containing a predetermined amount of solid particles. A step of filling a liquid crystal injection port with a stopper, and a step of curing the encapsulant to seal the liquid crystal injection port while suppressing shrinkage by the solid particles. Liquid crystal display device manufacturing method. 2. The resin includes at least one of a thermosetting resin and an ultraviolet curable resin, the solid particles include at least one of a glass fiber and a cured resin pellet, and the curing step includes heating or ultraviolet rays. The method further comprises the step of irradiating the resin to cure the uncured resin.
A method for manufacturing a liquid crystal display device according to item 1. 3. A liquid crystal display device comprising an ultraviolet curable resin, a curable resin containing at least one of the ultraviolet curable resin, and solid particles mixed in the curable resin. A sealant that seals the liquid crystal inlet. 4. The encapsulant according to claim 3, wherein the solid particles include at least one of glass fiber and cured resin pellets. 5. The encapsulant according to claim 3, which contains the solid particles in an amount of 2 to 5% by weight.